[Analysis on chemical and physical properties of Beijing super dust storm in spring of 2004].

On March 27, 2004 a super dust storm occurred in Beijing. The concentration of the aerosol and the element concentration of the aerosol were analyzed. The velocity of wind and radiation of ground were also measured. TSP increased 300 - 400 percent. PM2.5 increased 200 - 300 percent, but the concentration of the fine particle decreased. The elements like Na, Mg, Al, Mn and Fe mainly distribute in coarse particles. The contaminated elements such as Zn and Pb mainly distribute in fine particles. The contaminated elements mainly come from local source. The total radiation reduced 37.8 percent. With the increased of the velocity of the wind, the concentration of the coarse particle increased notability, the concentration of the fine particle decreased.

[The quantitative measurement of several main contaminants in sealed cabin].

OBJECTIVE: To establish a standardized analytical method of chromatography used for separating and determining six target contaminants including methyl alcohol, ethanol, glycol, acetic acid, acetone and benzene in space cabin simultaneously. METHOD: Optimal separating and examining conditions were determined through experiments by gas chromatography. Retention time was used to determine the nature of contamination and the method of extended standard to quantify accurately the six mixed contaminants. The method of five-point calibration was used. RESULT: Non-polar capillary GC column (30.00 m x 0.25 micrometers x 250 micrometers) was selected. Oven temperature was -30 degrees C initially and then hoisted to 80 degrees C at a rate of 4 degrees C/min, to 150 degrees C at 6 degrees C/min, to 250 degrees C at 10 degrees C/min and kept for 5 min. The temperature of flame ionization detector was 200 degrees C and that of back inlet adopting split mode was 150 degrees C. The linear correlation of calibration curve was satisfied and the precision of this method was high. CONCLUSION: Under optimal experimental conditions the chromatographic peaks of six contaminants were separated so completely that they were quantified accurately simultaneously. The results showed this method was simple, quick and accurate.